Appetite hormones and weight loss: leptin, ghrelin and hunger

Common misconceptions

“Appetite is determined by hormones, rather than willpower” may feel relieving if eating has often been treated as a character test. But making hormones the only decision-maker narrows the evidence again. The appetite-control review describes metabolic, behavioral and environmental influences. Reducing blame does not require finding a single replacement cause. It allows room to examine what happened without pretending that one mechanism explains every occasion on which someone wants food. [9]

Consider wanting a snack after seeing a food photograph following dinner, compared with feeling hungry because a meal was delayed. Both may be described as “wanting to eat,” yet the circumstances differ. Keeping those circumstances separate is an application of the review’s broader view of appetite. The appetite-control review does not quantify a photograph’s effect on appetite. This example proposes a way to observe daily situations, rather than claim a tested effect for that specific situation. [9]

Another misconception is that high leptin necessarily means fullness and high ghrelin necessarily means obesity. The reviews’ description of higher leptin and lower ghrelin in obesity does not fit that simple correspondence. Reduced responsiveness to leptin belongs in the explanation. Knowing that a hormone promotes or suppresses eating does not mean a blood value immediately reveals how a person eats, or what they should change at the next meal. [2][6]

The same caution applies to the leptin-to-ghrelin ratio. It was higher in the overweight and obesity group in the meal study, yet that group did not show significant differences between meal types. A larger ratio cannot simply be awarded a better score for appetite control. Giving a measurement an impressive name can make it feel like a grading system. The trial did not establish a passing grade that readers should try to reach. [10]

The study authors suggest that normal-weight men may experience greater satiety after a high-carbohydrate meal. The study centers on the hormone ratio, and its interpretation cannot be rewritten as a result showing that everyone ate less. It also gives no long-term weight-loss amount. Extending the finding to everyday meals in women, or to lasting weight reduction, crosses boundaries set by the participants and the observation period. [10]

A further misconception is that a diet acting on appetite hormones must be safe and sustainable over the long term. The appetite-control review discusses nutritional strategies including high-protein diets, but also describes uncertainties about physiological mechanisms and long-term safety. A short-term appetite change cannot settle the questions of long-term safety or weight maintenance. Before adopting the appealing name of a diet, ask which of those questions the cited evidence actually addressed. [9]

Protein and fiber deserve their own detailed treatment, as do sleep and appetite the next day, and appetite after exercise. Those subjects are covered in separate features in this series. The narrower task is to recognize when an explanation involving “hormones” merges different outcomes: concentration, reported feeling, food intake and body weight. Maintaining the distinctions is essential to reading the meal comparison accurately, even when the surrounding advice sounds familiar.

Studies should also be compared according to the questions they ask. A review discussing leptin’s role in long-term energy regulation and a meal trial following a post-meal ratio work at different timescales. A short-term response does not establish the same effect on long-term body weight. Conversely, an absence of a significant short-term difference does not show that the hormone has no role. Match the question and the observation period before treating findings as competing answers. [2][10]

Another study examined individual variation from a different angle. It enrolled 132 people with body mass indexes in the normal range and investigated variants in the ghrelin gene and the leptin receptor gene. A genetic variant is a difference in the sequence of a gene. The study examined relationships among those variants, dietary intake, subjective appetite and hormone concentrations. It was not an intervention establishing that a particular gene caused a participant to overeat. [18]

Dietary intake was assessed using 3-day diet records. Subjective appetite was measured with visual analogue scales, which let people indicate the degree of a sensation along a scale. Blood measurements were taken after a 12-hour fast and 120 minutes after a test meal. These methods give different kinds of information: records describe reported eating, the scale describes a person’s experience, and the blood sample describes measured biological values. Recording one of them does not automatically reveal the others. [18]

The researchers found a significant difference in fasting ghrelin between men and women. Participants carrying particular ghrelin gene variants had higher recorded consumption of fruit and bread or starch foods with added sugar, as well as higher measured ghrelin, than the comparison variant group. A particular leptin receptor gene variant was also associated with higher total sugar intake. The authors suggest that the variants may contribute to differences in response to a standardized meal and to sugar intake. [18]

The finding needs to retain its population and its uncertainty. These participants had normal-range body mass indexes. The reported results do not give the specific size of these differences or confidence intervals. The associations therefore cannot become a claim that avoiding fruit lowers ghrelin, a weight-loss plan for people with obesity, or a reason that adults generally need genetic testing. Sex and genetic variation were examined alongside intake and hormone measures, which distinguishes this study from the meal comparison conducted only in men. [18]

Read together, these studies offer different views rather than a personalized formula. The meal trial compares short-term responses under controlled energy conditions. The genetic study examines relationships across separately measured characteristics. Neither permits a household appetite feeling to serve as a diagnosis, and neither turns a measured hormone into a universal menu. What they offer is a more careful vocabulary for the question you are actually trying to answer. [10][18]

What you can do today

• At your next meal, replace a staple-only meal of rice or bread with a combination that includes a familiar protein-containing dish. Rebalance the meal instead of simply adding food. High-protein diets are discussed in appetite-control research, but no household protein target is established and long-term safety remains uncertain. [9]

• Compare the balance of your usual staple and accompanying dishes while keeping the total meal amount steady. In the 46-man trial, different meal compositions were matched at 450 kcal. Use the comparison principle, not 450 kcal as a personal meal limit; there was no significant meal-type difference in the overweight and obesity group. [10]

• Put the snack portion you intend to eat on a plate and sit down, instead of continuing to eat from its bag. This is a practical way to organize the eating environment, one of the influences discussed in appetite research. Its effect on weight loss or hormone levels was not tested in the review. [9]

• Keep a 3-day record of meals and snacks, using the recording period in the study as a practical example. Note the amount eaten and your feeling of fullness in separate fields. The study assessed dietary intake, subjective appetite and blood values separately; your record can organize observations but cannot measure hormones or establish a weight-loss effect. [18]

• If a new eating pattern makes you feel unwell, stop forcing yourself to continue and tell a doctor what you changed and how you feel. Do not combine very high protein intake, major carbohydrate restriction and intermittent fasting on the strength of hormone claims. The review leaves questions about mechanisms and long-term safety unresolved. [9]

Appetite awareness and a weekly movement slot at On the Shore Tachikawa

As you notice how hunger fits around meals, you can also plan a studio visit around eating and travel; On the Shore Tachikawa offers lesson choices and daily opening hours to consider.

For planning that time, the studio is open every day from 8:00 to 23:30. Its address is 3F Etoile Bldg, 2-14-10 Akebonocho, Tachikawa, Tokyo, a 1-minute walk from the North Exit of JR Tachikawa Station.

Many of our yoga instructors speak English, and the studio’s owner often helps guests from the US bases in English herself. Pregnant guests cannot join lava-stone hot yoga; room-temperature maternity yoga is available. Guests told by a doctor not to exercise cannot join.

On the Shore Tachikawa is a hot yoga studio with lava-stone plates. Alongside that setting, it offers room-temperature yoga, Pilates, women-only kickboxercise, boxercise, HIIT and personal training. Yoga alone includes more than 25 kinds of lessons.

A 60-minute trial yoga lesson costs ¥1,980 including tax, with rental of 2 bath towels, 1 face towel and a yoga mat included. To arrange a visit around meals and travel, consult the studio information, prices and trial booking.

References

2. The role of leptin and ghrelin in the regulation of food intake and body weight in humans: a review — M. D. Klok et al., 2007, Obesity Reviews. DOI: 10.1111/j.1467-789x.2006.00270.x
3. The melanocortin pathway and control of appetite- progress and therapeutic implications — G. Baldini et al., 2019, The Journal of endocrinology. DOI: 10.1530/joe-18-0596
4. Leptin and Obesity: Role and Clinical Implication — M. Obradović et al., 2021, Frontiers in Endocrinology. DOI: 10.3389/fendo.2021.585887
5. Appetite control: hormones or diet strategies? — R. H. Freire et al., 2020, Current Opinion in Clinical Nutrition and Metabolic Care. DOI: 10.1097/mco.0000000000000675
6. The relationship between the leptin/ghrelin ratio and meals with various macronutrient contents in men with different nutritional status: a randomized crossover study — Edyta Adamska-Patruno et al., 2018, Nutrition Journal. DOI: 10.1186/s12937-018-0427-x
7. LEAP-2: An Emerging Endogenous Ghrelin Receptor Antagonist in the Pathophysiology of Obesity — Xuehan Lu et al., 2021, Frontiers in Endocrinology. DOI: 10.3389/fendo.2021.717544
8. The cellular and molecular bases of leptin and ghrelin resistance in obesity — Hu-Xing Cui et al., 2017, Nature reviews. Endocrinology. DOI: 10.1038/nrendo.2016.222
9. Brain somatic cross-talk: Ghrelin, leptin and ultimate challengers of obesity — V. Popović et al., 2005, Nutritional Neuroscience. DOI: 10.1080/10284150400027107
10. Role of Leu72Met of GHRL and Gln223Arg of LEPR Variants on Food Intake, Subjective Appetite, and Hunger-Satiety Hormones — Tania Sánchez-Murguía et al., 2022, Nutrients. DOI: 10.3390/nu14102100
11. Endocrine regulation of energy metabolism: review of pathobiochemical and clinical chemical aspects of leptin, ghrelin, adiponectin, and resistin. — Ursula Meier et al., 2004, Clinical chemistry. DOI: 10.1373/clinchem.2004.032482

Information as of October 2026. For your own health, consult a doctor.